fix: sort Fee Type by name in LiveView and exports

Use Ash related-field sort (membership_fee_type.name) instead of
membership_fee_type_id so column order is alphabetical. Load
membership_fee_type when sorting by it even if column is hidden.
In-memory re-sort (Build) uses loaded fee type name.

lib/mv_web/live/member_live/index.ex

@@ -965,9 +965,10 @@ defmodule MvWeb.MemberLive.Index do
     query =
       Ash.Query.load(query, groups: [:id, :name, :slug])
 
-    # Load membership_fee_type when the column is visible
+    # Load membership_fee_type when the column is visible or when sorting by it
     query =
-      if :membership_fee_type in socket.assigns.member_fields_visible do
+      if :membership_fee_type in socket.assigns.member_fields_visible or
+           socket.assigns.sort_field in [:membership_fee_type, "membership_fee_type"] do
         Ash.Query.load(query, membership_fee_type: [:id, :name])
       else
         query
@@ -1133,9 +1134,9 @@ defmodule MvWeb.MemberLive.Index do
       field in [:groups, "groups"] ->
         {query, true}
 
-      # Membership fee type sort -> by FK at DB
+      # Membership fee type sort -> by related name at DB
       field in [:membership_fee_type, "membership_fee_type"] ->
-        {Ash.Query.sort(query, membership_fee_type_id: order), false}
+        {Ash.Query.sort(query, [{"membership_fee_type.name", order}]), false}
 
       # Custom field sort -> after load
       custom_field_sort?(field) ->
@@ -1777,6 +1778,15 @@ defmodule MvWeb.MemberLive.Index do
         end
       end)
 
+    # If fee type is visible but start_date was not in the list, append it
+    with_extras =
+      if :membership_fee_type in (member_fields_visible || []) and
+           :membership_fee_type not in with_extras do
+        with_extras ++ [:membership_fee_type]
+      else
+        with_extras
+      end
+
     if :groups in (member_fields_visible || []), do: with_extras ++ [:groups], else: with_extras
   end
 
@@ -1815,6 +1825,14 @@ defmodule MvWeb.MemberLive.Index do
         &expand_db_string_for_export(&1, membership_fee_type_visible, computed_strings)
       )
 
+    # If fee type is visible but start_date was not in the list, append it before computed/groups
+    db_with_extras =
+      if membership_fee_type_visible and "membership_fee_type" not in db_with_extras do
+        db_with_extras ++ ["membership_fee_type"]
+      else
+        db_with_extras
+      end
+
     # Any remaining computed fields not inserted above (future-proof)
     remaining_computed =
       computed_strings